stand/fdt: Fix loading of multiple fdt_overlays

[kevans]

Summary

fdt_load_dtb_overlays was written to unload previous overlay when a new valid one is come across. fdt_apply_overlays further down is written to iterate over all .dtbo's currently loaded and apply them one-by-one. Correct fdt_load_dtb_overlays to stop dropping valid overlays that were previously loaded and match expectations.

[imp]

my naive reading says this is right.

[manu]

Did you test multiple overlays targeting the same node ?
Last time I talk to gonzo@ about he came to the conclusion that we need to update libfdt in our tree and use their overlay implementation.

[gonzo]

In D13659#285514, @manu wrote:

Did you test multiple overlays targeting the same node ?
Last time I talk to gonzo@ about he came to the conclusion that we need to update libfdt in our tree and use their overlay implementation.

These are two independent issues: inability to modify same node and discarding previously loaded dtbo's. I think the latter was just a case of poorly applied copy-patse.

[kevans]

In D13659#285684, @gonzo wrote:

These are two independent issues: inability to modify same node and discarding previously loaded dtbo's. I think the latter was just a case of poorly applied copy-patse.

Sorry, I forgot to mention here- after D13663 and D13664, I've had no problems modifying the same node in different .dtbo